Embossed multi-ply tissue product

ABSTRACT

Disclosed are multi-ply embossed tissue products having improved softness, strength, embossment clarity and/or embossment height compared to prior art embossed tissue products. The multi-ply tissue products may comprise an embossed tissue ply having a basis weight less than about 25 grams per square meter (gsm) and relatively deep embossments, such as an embossment height from about 500 to about 1,000 gm and relatively narrow bottom portions compared to top portions. The combination of these elements provides an aesthetically pleasing and well-defined embossment, while improving important tissue product properties such as sheet and roll bulk and softness.

BACKGROUND

It is well known to emboss bond multiple plies of lightweight cellulosicmaterial to form tissue products such as bath tissues, facial tissues,paper towels, industrial wipers, foodservice wipers, napkins, medicalpads, and other similar products. The embossed tissue products maycomprise one, two, three or more plies. Embossing not only pliesmultiple webs together but may also impart the tissue product with anaesthetically pleasing pattern. Examples of apparatus and methods forembossing multi-ply paper products are disclosed, for example, in U.S.Pat. Nos. 6,733,866, 7,871,692 and 8,287,986 and U.S. Publication No.2012/0156447.

Embossing may also be used to alter or improve certain tissue productproperties such as sheet bulk and perceived softness. For example,tissue products manufactured using conventional creped wet presstechnology can be embossed subsequent to creping to improve bulk andperceived softness. Embossing often increases the surface area of thesheets my introducing a plurality of protuberances and thereby enhancesthe bulk and handfeel of the product. Examples of apparatus and methodsfor embossing multi-ply paper products to improve handfeel and bulk aredisclosed, for example, in U.S. Publication Nos. 2005/0103456,2018/0142422 and 2018/0135254.

Often tissue products marketed in rolls, contain a specified number ofsheets per roll. Tissue embossed in conventional patterns of dotembossments, when packaged in roll form, exhibit a tendency to benon-uniform in appearance often due compressing of the embossments asthe sheet is wound onto the roll, detracting from the appearance of therolls.

SUMMARY

The present inventors have now discovered novel embossed multi-plytissue products having improved softness, strength, embossment clarityand/or embossment height compared to prior art embossed tissue products.For example, the multi-ply tissue products of the present invention maycomprise a plurality of embossments that are relatively deep and haverelatively narrow bottom portions compared to top portions. In aparticularly preferred embodiment, the product may comprise an embossedply having a plurality of dot embossments disposed thereon, the dotembossments having a height—defined as H₁₀₀ and measured as describedherein—greater than about 500 μm, such as from about 500 to about 1,000μm and relatively narrow bottom portions compared to top portions suchas a ratio of the average width at 100% height (W₁₀₀) to the averagewidth at 25% height (W₂₅) greater than about 3.0, such as from about 3.0to about 4.0. The combination of these elements provides anaesthetically pleasing and well-defined embossment, while improvingimportant tissue product properties such as sheet and roll bulk andsoftness.

In other embodiments the present invention provides a multi-ply tissueproduct comprising a top ply having a first surface having a pluralityof discrete, spaced apart, dot embossments disposed thereon and aplurality of dome-like structures disposed between the spaced apart dotembossments and a bottom ply having a first surface having a pluralityof discrete embossments disposed thereon, wherein the dot embossmentshave a height (H₁₀₀) greater than 500 μm and an average width at 25%height (W₂₅) less than about 600 μm.

In still other embodiments the present invention provides a multi-plytissue product, such as a product comprising three, four, five or sixplies, wherein the basis weight of each of the plies is less than about25 grams per square meter (gsm), such as from about 10 to about 25 gsmand more preferably from about 15 to about 20 gsm, and at least theupper most ply comprises a plurality of spaced apart dot embossmentshaving a height (H₁₀₀) greater than 500 μm and an average width at 25%height (W₂₅) less than about 600 μm.

In other embodiments the present invention provides a multi-ply tissueproduct comprising a first ply having an unembossed region having anupper surface lying in a first tissue product surface plane, a pluralityof spaced apart first dot embossments and a dome-like structure disposedbetween at least two spaced apart first dot embossments, the dome-likestructure having an upper surface lying in a second tissue productsurface plane, wherein the second tissue product surface plane is atleast 100 μm above the first tissue product surface plane. In certaininstances, the dome-like structure may be supported by an embossmentdisposed on a second ply having an embossment that nests into thedome-like structure and is bounded by the first and second discreteembossments disposed on the first ply. In other instances, the tissueproduct may contain a third ply disposed between the first and secondplies, wherein the third ply comprises embossments registered with thefirst and second discrete embossments of the first ply and the third plyis bonded to the first ply.

In yet other embodiments the invention relates to a method of producinga tissue product comprising the steps of: (a) providing a firstembossing station with a first embossing roll having a first patterndisposed thereon and a first counter roll, the first embossing roll andfirst counter roll defining a first nip there between; (b) providing asecond embossing station with a second embossing roll having a secondpattern disposed thereon and a second counter roll, the second embossingroll and second counter roll defining a second nip there between; (c)providing a marrying roll in opposition to the first counter roll todefine a third nip there between; (d) synchronizing the rotation of thefirst and second embossing rolls; (d) directing a first and a secondtissue ply into the first nip; (d) applying an adhesive to the surfaceof the second ply; (e) directing a third tissue ply into the second nip;(e) directing the three plies through the third nip thereby adhesivelyattaching the third ply to the second ply.

The device for manufacturing a tissue product includes a first embossingstation with a first embossing roll and a first anvil roll, a secondembossing station with a second embossing roll and a second anvil roll,the second anvil roll being a rubber roll or a steel roll, an adhesiveapplicator roll running against the first embossing roll and a marryingroll running against the first embossing roll. The first embossing rolland the second embossing roll are adapted to run in registration withone another. This is a relatively simple device which can be used toemboss the top and bottom plies and to combine the plies in a nestedconfiguration in the nip between the first embossing roll and a marryingroll. In order to realize the desired nested configuration with theembossments applied to the top ply bounding the embossments applied tothe bottom such that a dome-like structure is formed between theembossments of the first ply and supported by the embossments of thesecond ply, the first embossing station and second embossing station areregistered with one another such that the positional relationship of thefirst embossing protuberances and the second embossing protuberances canbe predetermined in the final product.

In still other embodiments the present invention provides a tissueproduct, such as a bath tissue product and more particularly a multi-plybath tissue product, having a basis weight from about 40 to about 60grams per square meter (gsm), wherein each of the plies have a basisweight less than about 25 gsm and more preferably less than about 20gsm, such as from about 10 to about 25 gsm and more preferably fromabout 15 to about 20 gsm, the product having a geometric mean tensilestrength less than about 800 g/3″, such as from about 800 to about 1,700g/3″. The tissue product includes at least one top ply, at least onemiddle ply and at least one bottom ply. The term “at least one” shouldindicate that the top ply, middle ply and bottom ply can in themselvesbe a multi-ply structure, respectively. However, if, e.g., a double plybottom ply is used, such plies are not processed separately whenembossing and bonding together the tissue product. In the followingdescription, when reference is made to the top ply, the middle ply orthe bottom ply, this includes the above-described option that theseplies are made up of more than one tissue ply.

In yet other embodiments the top ply of a multi-ply tissue product ofthe present invention is provided with an embossing pattern comprising aplurality of discrete first embossments and dome-like structuresdisposed between the first embossments and the bottom ply is embossedwith second embossments that nest into the dome-like structures disposedbetween first embossments of the top ply. In particular instances thesecond embossments are shaped so as to be substantially complementary tothe dome-like structure disposed on the top ply.

In other embodiments the present invention provides a tissue productcomprising a first surface having a plurality of first embossmentsdisposed thereon and a second surface having a plurality of secondembossments disposed thereon, wherein the first and second embossmentsare discrete and differ in at least height and area. In certainpreferred embodiments the first embossments may be dot embossmentshaving a relatively small surface area and good height and the secondembossments may be larger, more elaborately shaped embossments havingless height. Further, the first side may comprise dome-like structuresbounded by the first embossments, wherein the dome-like structuresprovide a soft handfeel and a cushiony appearance.

In still other embodiments the invention provides a tissue productcomprising a first surface having a plurality of dot embossmentsdisposed in a pattern and bounding a dome-like structure, the dome-likestructure comprises at least about 2 percent of the projected surfacearea of the product, such as from about 2 to about 10 percent, such asfrom about 5 to about 8 percent. This embossing pattern forms cushionsthat are surrounded by regions of compressed material. Generally, thedot embossments of the present invention have a shape of interruptedlines or a shape of small individual points or spots that may bearranged relative to one another to provide the appearance of a line ora design. The dot embossments need not have a circular cross-sectionalshape at the tissue surface and in certain instances may have acurvilinear or rectilinear cross-sectional shape. For example, the dotembossments may have a rectilinear cross-sectional shape that may bearranged to form the appearance of dashed lines. In other instances, thedot embossment cross-sectional shape may be a circle, an oval, anellipse, a square, or a triangle.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is perspective view of a rolled tissue product according to oneembodiment of the present invention;

FIG. 2 is a top plan view of the tissue product of FIG. 1;

FIG. 3 is a schematic cross-sectional view of a three-ply tissue productaccording to one embodiment of the present invention;

FIG. 4A is a 3-D surface profile of a tissue product according to oneembodiment of the present invention, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 4B is a 2-D image of the product of FIG. 4A and a plot of thesurface topography through line A-A, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 4C is a cross-sectional height profile of the product of FIG. 4Bthrough line A-A;

FIG. 5A is a 3-D surface profile of a tissue product according toanother embodiment of the present invention, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 5B is a 2-D image of the product of FIG. 5A and a plot of thesurface topography through line A-A, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 5C is a cross-sectional height profile of the product of FIG. 5Bthrough line A-A;

FIG. 6A is a 3-D surface profile of a tissue product according toanother embodiment of the present invention, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 6B is a 2-D image of the product of FIG. 6A and a plot of thesurface topography through line A-A, the image was taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation (Osaka,Japan) at a magnification of X100;

FIG. 6C is a cross-sectional height profile of the product of FIG. 6Bthrough line A-A;

FIG. 7 is a schematic of a process useful in the manufacture of athree-ply tissue product according to the present invention;

FIG. 8 is a schematic of a process useful in the manufacture of afour-ply tissue product according to the present invention;

FIG. 9 is a top plan view of a portion of a patterned roll useful in theinvention;

FIG. 10 is a detailed view of an element disposed on the patterned rollof FIG. 9;

FIG. 11 is a cross-sectional view of the element of FIG. 10 through lineFIG. 11-FIG. 11;

FIG. 12 is a cross-sectional view of the element of FIG. 10 through lineFIG. 12-FIG. 12;

FIG. 13 is a top plan view of a portion of a patterned roll useful inthe invention;

FIG. 14 is a plot of the ratio of W₁₀₀ to W₂₅ (Y-axis) versus H₁₀₀(X-axis) for several prior art and inventive tissue products;

FIG. 15 is a plot of the ratio of W₅₀ to W₂₅ (Y-axis) versus H₁₀₀(X-axis) for several prior art and inventive tissue products;

FIG. 16 is a plot of the ratio of W₁₀₀ to W₅₀ (Y-axis) versus H₁₀₀(X-axis) for several prior art and inventive tissue products; and

FIG. 17 is a plot of W₅₀ (Y-axis) versus H₅₀ (X-axis) for several priorart and inventive tissue products.

DEFINITIONS

As used herein the term “tissue web” refers to a structure comprising aplurality of fibers such as, for example, papermaking fibers and moreparticularly pulp fibers, including both wood and non-wood pulp fibers,and synthetic staple fibers. A non-limiting example of a tissue web is awet-laid sheet material comprising pulp fibers.

As used herein the term “tissue product” refers to products made fromtissue webs and includes, bath tissues, facial tissues, paper towels,industrial wipers, foodservice wipers, napkins, medical pads, and othersimilar products. Tissue products may comprise one, two, three or moreplies.

As used herein the term “layer” refers to a plurality of strata offibers, chemical treatments, or the like, within a ply.

The term “ply” refers to a discrete product element. Individual pliesmay be arranged in juxtaposition to each other. The term may refer to aplurality of web-like components such as in a multi-ply facial tissue,bath tissue, paper towel, wipe, or napkin.

As used herein, the term “basis weight” generally refers to the bone dryweight per unit area of a tissue and is generally expressed as grams persquare meter (gsm). Basis weight is measured using TAPPI test methodT-220.

As used herein, the term “caliper” is the representative thickness of asingle sheet (caliper of tissue products comprising two or more plies isthe thickness of a single sheet of tissue product comprising all plies)measured in accordance with TAPPI test method T402 using an EMVECO 200-AMicrogage automated micrometer (EMVECO, Inc., Newberg, OR). Themicrometer has an anvil diameter of 2.22 inches (56.4 mm) and an anvilpressure of 132 grams per square inch (per 6.45 square centimeters) (2.0kPa).

As used herein, the term “sheet bulk” refers to the quotient of thecaliper (μm) divided by the bone dry basis weight (gsm). The resultingsheet bulk is expressed in cubic centimeters per gram (cc/g). Tissueproducts prepared according to the present invention generally have asheet bulk greater than about 7.0 cc/g, more preferably greater thanabout 8.0 cc/g and still more preferably greater than about 9.0 cc/g,such as from about 7.00 to about 11.0 cc/g, such as from about 8.00 toabout 10.0 cc/g.

As used herein, the term “slope” refers to the slope of the lineresulting from plotting tensile versus stretch and is an output of theMTS TestWorks™ in the course of determining the tensile strength asdescribed in the Test Methods section herein. Slope is reported in theunits of grams (g) per unit of sample width (inches) and is measured asthe gradient of the least-squares line fitted to the load-correctedstrain points falling between a specimen-generated force of 70 to 157grams (0.687 to 1.540 N) divided by the specimen width. Slopes aregenerally reported herein as having units of kilograms per sample width,such as kg/3″.

As used herein, the term “geometric mean slope” (GM Slope) generallyrefers to the square root of the product of machine direction slope andcross-machine direction slope. GM Slope generally is expressed in unitsof kg.

As used herein, the terms “geometric mean tensile” (GMT) refers to thesquare root of the product of the machine direction tensile strength andthe cross-machine direction tensile strength of the web.

As used therein the term “dot embossment” means an embossment thatexhibits an aspect ratio of about 1:1. Non-limiting examples of dotembossments are embossments having a circular, oval, square, ortriangular cross-sectional shape.

As used herein the term “Average Height at 100%” (H₁₀₀) for a givenembossment 24 (as illustrated in FIG. 4C) refers to the average of thez-directional distance between the embossment minimum 45 and theleft-most embossment maximum 47 (H1) and the z-directional distancebetween the embossment minimum 45 and the right-most embossment maximum49 (H2). H₁₀₀ typically has units of microns (μm) and is measured asdescribed in the Test Methods section below.

As used herein the term “Average Height at 50%” (H₅₀) for a givenembossment 24 (as illustrated in FIG. 5C) refers to the average of thez-directional distance (H3) between the midpoint M1 of a straight lineH1 intersecting the embossment minimum 45 and the left-most embossmentmaximum 47 and the z-directional distance (H4) between the midpoint M2of the a straight line H2 intersecting the embossment minimum 45 and theright-most embossment maximum 49. H₅₀ typically has units of microns(μm) and is measured as described in the Test Methods section below.

As used herein the term “Average Height at 25%” (H₂₅) for a givenembossment 24 (as illustrated in FIG. 5C) refers to the average of thez-directional distance (H5) between a point Q1 at 25% of the straightline H1 intersecting the embossment minimum 45 and the left-mostembossment maximum 47 and the z-directional distance (H6) between apoint Q2 at 25% of the straight line H2 intersecting the embossmentminimum 45 and the right-most embossment maximum 49. H₂₅ typically hasunits of microns (μm) and is measured as described in the Test Methodssection below.

As used herein the term “Area at 100%” (A₁₀₀) for a given embossment 24(as illustrated in FIG. 4C) refers to the area A1 of the embossment 24below a straight line 56 intersecting the right and left-most embossmentmaximums 47, 49. A₁₀₀ typically has units of square microns (μm²) and ismeasured as described in the Test Methods section below.

As used herein the term “Area at 50%” (A₅₀) for a given embossment 24(as illustrated in FIG. 5C) refers to the area A2 of the embossment 24below a straight line 58 intersecting midpoints M1, M2. A₅₀ typicallyhas units of square microns (μm²) and is measured as described in theTest Methods section below.

As used herein the term “Area at 25%” (A₂₅) for a given embossment 24(as illustrated in FIG. 5C) refers to the area A3 of the embossment 24below a straight line 60 intersecting a points Q1 and Q2. A₂₅ typicallyhas units of square microns (μm²) and is measured as described in theTest Methods section below.

As used here the term “Average Width at 100% Height” (W₁₀₀) for a givenembossment 24 (as illustrated in FIG. 5C) generally refers to the lengthof a straight line 56 intersecting the right and left-most embossmentmaximums 47, 49. W₁₀₀ may be calculated by dividing the Area at 100%(A₁₀₀) by the Average Height at 100% (H₁₀₀):

$W_{100} = \frac{A_{100}}{H_{100}}$

W₁₀₀ typically has units of microns (μm) and is measured as described inthe Test Methods section below.

As used here the term “Average Width at 50% Height” (W₅₀) generallyrefers to the average width of the embossment near its midpoint. For agiven embossment 24 (as illustrated in FIG. 5C) W₅₀ is generally thelength of a straight line 58 intersecting midpoints M1, M2. W₅₀ may becalculated by dividing the Area at 50% (A₅₀) by the Average Height at50% (H₅₀):

$W_{50} = \frac{A_{50}}{H_{50}}$

W₅₀ typically has units of microns (μm) and is measured as described inthe Test Methods section below.

As used here the term “Average Width at 25% Height” (W₂₅) generallyrefers to the average width of the embossment at 25% of its height. Forexample, as illustrated in FIG. 5C, W₂₅ is the length of the straightline 60 intersecting points Q1 and Q2, which are 25% of the height ofthe right and left-most embossment maximums. W₂₅ may be calculated bydividing the Area at 25% (A₂₅) by the Average Height at 25% (H₂₅):

$W_{25} = \frac{A_{25}}{H_{25}}$

W₅₀ typically has units of microns pm and is measured as described inthe Test Methods section below.

DETAILED DESCRIPTION

The present invention provides a multi-ply embossed tissue producthaving improved softness, strength, embossment clarity and/or embossmentheight compared to prior art embossed tissue products. Accordingly, inone embodiment the present invention provides a multi-ply tissue productcomprising an embossed tissue ply having a basis weight less than about25 grams per square meter (gsm), such as from about 10 to about 25 gsmand more preferably from about 15 to about 20 gsm, and a plurality ofembossments disposed thereon.

Preferably the embossments are shaped and sized to provide the tissueproduct with improved pattern clarity and definition. As such, theembossments may be relatively deep having a H₁₀₀, measured as describedherein, greater than about 500 μm, such as from about 500 to about 1,000μm. Further, the embossments may have relatively wide top portionscompared to the bottom portions, which are relatively narrow. Therelative dimension of the embossment top and bottom portions may bedefined as the ratio of W₁₀₀ to W₂₅ and measured as described herein.For example, the product may comprise a plurality of embossments havinga ratio of W₁₀₀ to W₂₅ greater than about 3.0, such as from about 3.0 toabout 4.0. The combination of these elements provides an aestheticallypleasing and well-defined embossment, while improving important tissueproduct properties such as sheet and roll bulk and softness.

The tissue products of the present invention generally comprise two,three or four tissue plies made by well-known wet-laid papermakingprocesses such as, for example, creped wet pressed, modified wetpressed, creped through-air dried (CTAD) or uncreped through-air dried(UCTAD). For example, creped tissue webs may be formed using either awet pressed or a modified wet pressed process such as those disclosed inU.S. Pat. Nos. 3,953,638, 5,324,575 and 6,080,279, the disclosures ofwhich are incorporated herein in a manner consistent with the instantapplication. In these processes the embryonic tissue web is transferredto a Yankee dryer, which completes the drying process, and then crepedfrom the Yankee surface using a doctor blade or other suitable device.

In other instances, the tissue plies may be manufactured by athrough-air dried process known in the art. In such processes theembryonic web is noncompressively dried. For example, textured tissueplies may be formed by either creped or uncreped through-air driedprocesses. Particularly preferred are uncreped through-air dried webs,such as those described in U.S. Pat. No. 5,779,860, the contents ofwhich are incorporated herein in a manner consistent with the presentdisclosure.

In still other instances the tissue plies may be manufactured by aprocess including the step of using pressure, vacuum, or air flowthrough the wet web (or a combination of these) to conform the wet webinto a shaped fabric and subsequently drying the shaped sheet using aYankee dryer, or series of steam heated dryers, or some other means,including but not limited to tissue made using the ATMOS processdeveloped by Voith or the NTT process developed by Metso; or fabriccreped tissue, made using a process including the step of transferringthe wet web from a carrying surface (belt, fabric, felt, or roll) movingat one speed to a fabric moving at a slower speed (at least 5 percentslower) and subsequently drying the sheet. Those skilled in the art willrecognize that these processes are not mutually exclusive, e.g., anuncreped TAD process may include a fabric crepe step in the process.

The instant multi-ply tissue product may be constructed from two or moreplies that are manufactured using the same or different tissue makingtechniques. In a particularly preferred embodiment, the multi-ply tissueproduct comprises three plies where each of the plies comprises awet-pressed tissue ply, where each ply has a basis weight greater thanabout 10.0 gsm, such as from about 10.0 to about 20.0 gsm, such as fromabout 12.0 to about 16.0 gsm.

Regardless of the tissue making process used to produce the individualplies, the resulting multi-ply tissue product has a first surface havinga plurality of first embossments. As shown in FIG. 1, the tissue productmay be in the form of a rolled tissue product 10 comprising an embossedmulti-ply tissue sheet 20 spirally wound around a core 15. The tissuesheet 20 has a first surface 22 having a plurality of first embossments24 disposed thereon. The plurality of first embossments 24 are similarlyshaped and sized, having substantially similar surface area which, incertain instances, may range from about 0.070 to about 0.380 mm², suchas from about 0.125 to about 0.280 mm².

The first embossments 24 may be a dot emboss element having a generallycircular shape at the tissue surface 22. A dot emboss element, such asthe first embossment 24, can be characterized by having a depth relativeto the surface of the respective sheet surface 22 and a total embossmentlength to total embossment width (or an aspect ratio) of about 1. Thefirst embossments 24 may be further arranged to provide the appearanceof discontinuous lines 30, which are further arranged to form anembossed element 32 in the form of a flower. The embossed elements 32are further arranged relative to one another to form a pattern 40 on thetissue surface 22.

Generally, the embossing pattern may comprise a plurality of embossingelements 32 having the same, similar or different shapes. Suitableembossing element shapes may include, for example, geometric shapes,organic shapes, abstract shapes, characters, and branding. In certaininstances, the embossing elements may be geometric shapes, such assquares, octagons, pentagons, diamonds, triangles, circles, and thelike. In other instances, the embossing element may be an organic shapethat is illustrative of a natural object such as a leaf, a flower, asnowflake, or the like. In still other instances the embossing elementmay be an abstract shape, which may be derived from an actual object butnot be immediately recognizable as such by a consumer.

With continued reference to FIG. 1, the first embossments 24 arearranged to provide the appearance of a discontinuous line 30 whichdelimits a dome-like structure 36 disposed between the spaced apartembossments, such as embossments 24 a and 24 b. The dome-like structures36 may provide the tissue product 10 with a cushiony appearance. Incertain instances, the dome-like structures may be entirely bounded byfirst embossments, which may be arranged to form a closed line element,and have an upper surface lying in a first surface plane above the uppersurface of the first embossments. In other instances, the embossedelements 32 may be spaced apart from one another to define unembossedregions 38 there between. The unembossed regions 38 may have a surfacelying in a second surface plane, which may be below the first surfaceplane defined by the upper surface of the dome-like structure.

With reference now to FIG. 2, the embossing pattern 40 may comprise aplurality of similarly shaped and sized embossing elements 32 having anorganic shape, such as a flower or a leaf. The non-limiting flowershaped embossing elements 32 a, 32 b have an axis of symmetry 37 that isgenerally aligned in the machine direction (MD) and divides the elementinto substantially equal first and second halves 46, 48.

The embossing elements may be arranged and sized to provide the productwith an embossed pattern having a total embossed surface area rangingfrom about 5 to about 40 percent, more preferably ranging from about 8to about 35 percent, even more preferably ranging from about 20 to about25 percent. In a preferred embodiment, only embossed elements that arecompletely disposed upon the tissue sheet surface are utilized for thecalculation of total embossed area.

Without desiring to be bound by theory, providing a tissue producthaving an embossed area ranging from about 5 about 40 percent, and morepreferably from about 8 to about 25 percent, and an embossed patternconsisting essentially of organic shaped embossed elements formed fromdot emboss elements communicates to the consumer that the product issoft and cushiony. Additionally, at the foregoing embossed areas andshapes the emboss pattern has an aesthetic quality that does not appearoverly complicated but simplistic and natural.

The multi-ply embossed tissue products of the present invention may havea basis weight from about 20 to about 80 gsm, such as from about 30 toabout 65 gsm, such as from about 42 to about 60 gsm. In certaininstances, the multi-ply embossed tissue products may comprise two,three or four tissue plies where the basis weight of each individualtissue plie is less than about 25 gsm, such as from about 10 to about 20gsm, such as from about 10 to about 15 gsm.

In certain instances, the multi-ply embossed tissue products of thepresent invention may have a geometric mean tensile (GMT) strength fromabout 800 to about 1,800 g/3″, such as from about 800 to about 1,600g/3″, such as from about 800 to about 1,500 g/3″. In certain instances,the multi-ply embossed tissue products may comprise two, three or fourtissue plies where the GMT of each individual tissue plie is less thanabout 600 g/3″, such as from about 200 to about 425 g/3″, such as fromabout 350 to about 550 g/3″.

In other instances, the multi-ply embossed tissue products of thepresent invention may have a sheet bulk greater than about 7.00 cc/g,such as from about 7.00 to about 11.0 cc/g, such as from about 8.00 toabout 10.0 cc/g. In certain instances, at the foregoing sheet bulks, thetissue products may have a sheet caliper greater than about 1,000 μm,such as from about 1,000 to about 2,000 μm, such as from about 1,000 toabout 1,800 μm.

The foregoing multi-ply tissue products may be converted into rolledtissue products, such as rolled bath tissue products, comprising amulti-ply embossed tissue web spirally wound about a core. Such rolledtissue products may comprise a plurality of connected, but perforated,multi-ply tissue sheets that may be separated from adjacent sheets.Rolled tissue product may have a roll bulk greater than about 8.00 cc/g,such as from about 8.50 to about 15.0 cc/g, such as from about 9.00 toabout 13.0 cc/g.

In certain instances, the present invention provides a multi-ply tissueproduct comprising a first embossed tissue ply having a basis weightfrom about 13 to about 20 gsm and a first and a second surface, thefirst surface having a plurality of dot embossments disposed thereon.The dot embossments are arranged to form an embossed element, aplurality of which may further be arranged to form an embossed patternon the first surface of the first embossed tissue ply. The dotembossments forming the element may be separated and spaced apart fromone another to define cushion regions there between.

The tissue product may comprise a cushion region supported by apillow-like embossment disposed on an opposing tissue ply forming aportion of the multi-ply tissue product, as will be described in moredetail below. The existence of the cushion regions, which are supportedby opposing pillow-like embossments generates the visual appearance ofsoft cushions and improves the perceived softness of the product.

Moreover, the product has good mechanical properties, such as GMT, aswell as good caliper and bulk. The properties of three- and four-plytissue products prepared according to the present invention aresummarized in Table 1, below.

TABLE 1 Inventive Four-Ply Inventive Three-Ply Rolled Tissue ProductRolled Tissue Product Basis Wt. (gsm) 58 50 Sheet caliper (mm) 0.6940.533 Sheet bulk (cc/g) 11.2 9.9 Roll bulk (cc/g) 10.2 10.1 KershawFirmness (mm) 9.30 10.51

With reference now to FIG. 3, a schematic cross-sectional view of atissue product 20 according to one embodiment of the present inventionis illustrated. The multi-ply tissue product 20 comprises a first, uppermost, ply 31, a middle ply 33 and a bottom ply 35. The product 20 has anupper surface 22 formed from the first ply 31 and an opposed bottomsurface 23 formed from the bottom ply 35. The top ply 31 is providedwith embossments 24 a, 24 b which delimit a dome-like structure 36disposed there between. In certain instances, the top ply can beprovided with a micro-embossing pattern (not shown in FIG. 3), such as apattern having a dot density of more than 30 dots per cm².

The embossments 24 a, 24 b may have an elongated shape having opposedside walls 41, 43 and a bottom portion 45, which may be substantiallyplanar or curvilinear. The embossments 24 have an embossment height (H)that is generally the distance between the upper surface plane 50 of anunembossed region 38 and the surface plane 52 of the upper surface ofthe embossment bottom portion 45.

The embossments may be relatively wide near the tissue surface. Forexample, the embossments may have a cross-sectional dimension near theupper surface of the product from about 0.070 and about 0.40 mm². Thecross-sectional geometry of the embossments at the surface of the tissueproduct may be selected from a variety of geometric shapes, such as, forexample, circular or oval. In a particularly preferred embodiment, theembossments are similarly shaped and have a circular cross-sectionalshape.

Between the spaced apart first embossments 24 a, 24 b are dome-likestructures 36. The dome-like structure 36 has an upper surface lying ina second upper surface plane 54. In certain instances, the second uppersurface plane 54 may lie above the first upper surface plane 50,providing the tissue product upper surface with at least two differentplanes. For example, the tissue product 20 may comprise unembossedregions 38 having an upper surface lying in a first surface plane 50 anddome-like structures 36 disposed between embossments 24 a, 24 b andlying in a second surface plane 54, wherein the second tissue productsurface plane 54 is above the first tissue product surface plane 50.

As will be discussed in more detailed below, in certain instances, toelevate the dome-like structure 36 above the unembossed area 38, thestructure 36 may be supported by a second embossment 25. The secondembossment 25 may be disposed on a third (bottom) tissue ply 35 andregistered with the first embossments 24 a, 24 b, such that the secondembossment 25 nests into the dome-like structure 36 and is bounded bythe first embossments 24 a, 24 b.

The product may further comprise a middle ply. The middle ply maycomprise embossments arranged in an embossing pattern similar to thefirst ply embossing pattern. The first and second plies may be pliedtogether such that the embossments are registered with one another. Theembossments may be registered with one another by embossing the firstand second plies in a single step. For example, the first and secondplies may be plied together and then passed through a single embossingnip. In certain preferred embodiments the top and middle plies are notadhesively attached to one another, rather the plies are attachedmechanically by embossing. In a particularly preferred embodiment, suchas that illustrated in FIG. 3, the middle ply 33 is attached to thethird (bottom) ply 35, such as by an adhesive, at discrete points 27 a,27 b.

With continued reference to FIG. 3, the third ply 35 comprises aplurality of second embossments 25. The embossed first (top) 31 andsecond (middle) plies 33 are plied in registration with the third(bottom) ply 35 such that the second embossment 25 is disposed betweenthe first embossments 24 a, 24 a. In this manner the second embossments25 is arranged and sized so as to nest into the dome-like structure 36.In the embodiment illustrated in FIG. 3, only one second embossment 25is nested with the dome-like structure. In other embodiments, however,the third ply may comprise more than one second embossment that has beensized and arranged to support the dome-like structure when the plies arearranged in a nested configuration.

In certain instances, such as illustrated in FIG. 3, the product 20 maycomprise first and second surfaces 22, 23 having different embossingpatterns and textures. More particularly, the first surface 22 maycomprise a plurality of first embossments 24 a, 24 b that are spacedapart from one another and define dome-like structures 36 there between.The second surface 23 comprises second embossments 25, which arepreferably differently shaped than the first embossments 24. Forexample, the first embossments 24 and second embossments 25 may differin terms of shape, height, depth and/or area. In certain preferredembodiments the first embossments may be dot embossments havingrelatively small surface area and relatively deep and the secondembossments may have a greater surface area and not as deep.

With reference now to FIGS. 4A-4C a tissue product 20 prepared accordingto the present invention is illustrated. FIG. 4A is a 3-D height profileof a first tissue product surface 22 comprising a plurality of firstembossments 24 a, 24 b, which are spaced apart and define dome-likestructures 36 there between having an upper surface lying in an uppersurface plane. The first surface 22 also includes unembossed regions 38.Generally, the unembossed regions 38 have a surface lying in a surfaceplane below the surface plane of the dome-like structures. In theillustrated embodiment the upper surface of the dome-like structureslies about 200 μm above the surface of the unembossed regions andprovides the tissue product with a cushiony appearance.

As illustrated in the cross-sectional profile of FIGS. 4B and 4C, thefirst embossments are generally deep. In certain instances, the firstembossments may have a H₁₀₀ greater than about 500 μm, such as greaterthan about 600 μm and more preferably greater than about 700 μm and evenmore preferably greater than about 800 μm, such as from about 500 toabout 1,200 μm, such as from about 700 to about 1,000 μm. Further, thefirst embossments may have relatively steep sidewalls and relativelynarrow lower portions. In this manner, the first embossments may have aH₅₀ greater than about 350 μm, such as from about 350 to about 500 μm,such as from about 400 to about 500 μm, and a W₅₀ less than about 500μm, such as from about 300 to about 500 μm, such as from about 300 toabout 400 μm.

With reference now to FIGS. 5A-5C another tissue product 20 preparedaccording to the present invention is illustrated. FIG. 5A is a 3-Dheight profile of the first tissue product surface comprising aplurality of first embossments 24 a, 24 b, which are spaced apart anddefine dome-like structures 36 there between. The first surface 22 alsoincludes unembossed regions 38. Generally, the unembossed regions 38have a surface lying in a surface plane below the surface plane definedby the upper surface of the dome-like structures. In the illustratedembodiment, the upper surface of the dome-like structures lies about 200μm above the surface of the unembossed regions and provides the tissueproduct with a cushiony appearance.

As illustrated in the cross-sectional profile of FIGS. 5B and 5C, thefirst embossments are generally deep. For example, the first embossmentsmay have a H₁₀₀ from about 700 to about 1,000 μm. Further, the firstembossments may have lower portions that are relatively narrow, such asW₂₅ less than about 600 μm, such as from about 400 to about 600 μm andupper portions that are relatively broad, such as W₁₀₀ greater thanabout 1,500 μm, such as from about 1,500 to about 2,500 μm. For example,in certain instances the first embossments may have a H₅₀ greater thanabout 350 μm, such as from about 350 to about 500 μm, such as from about400 to about 500 μm, and a W₅₀ less than about 500 μm, such as fromabout 300 to about 500 μm, such as from about 300 to about 400 μm.

With reference to FIGS. 6A-6C another tissue product prepared accordingto the present invention is illustrated. FIG. 6A is a 3-D height profileof the first surface of the tissue product comprising a plurality offirst embossments 24, which are spaced apart and define dome-likestructures 36 there between. The first surface also includes unembossedregions 38. In the illustrated embodiment, the upper surface of thedome-like structures lies from about 120 to about 300 μm above thesurface of the unembossed regions and provides the tissue product with acushiony appearance. In certain preferred embodiments, the upper surfaceof the dome-like structures lies about 200 μm above the surface of theunembossed regions.

As illustrated in FIGS. 6B and 6C, the first embossments are generallydeep, such as a H₁₀₀ greater than about 500 μm and more preferablygreater than about 600 μm and still more preferably greater than about700 μm, such as from about 700 to about 1,000 μm.

Generally, the embossed tissue products are an improvement over priorart embossed tissue products, particularly in terms of embossmentpattern clarity and definition. Without being bound by any particulartheory, it is believed that the improvement in pattern clarity anddefinition is attributable, in-part, to first embossments that arerelatively deep with broad top portions and relatively narrow bottomportions. For example, the first embossments may have a H₁₀₀ (ameasurement of embossment depth) from about 700 to about 1,000 μm and aW₂₅ (a measurement of size of the embossment at is bottom portion) lessthan about 600 μm, such as less than about 500 μm, such as from about300 to about 600 μm. In other instances, the first embossments may haveratios of W₁₀₀ to W₂₅ (measurements of the relative size of anembossment at its top and bottom portions) greater than about 3.0, suchas greater than about 3.25, such as greater than about 3.5, such as fromabout 3.0 to about 4.0.

The novel features of the present tissue products compared to those ofthe prior art are further summarized in Table 2, below.

TABLE 2 H₁₀₀ H₅₀ H₂₅ W₁₀₀ W₅₀ W₂₅ Product Product Type Mfg. (μm) (μm)(μm) (μm) (μm) (μm) W₁₀₀:W₅₀ W₁₀₀:W₂₅ W₅₀:W₂₅ Just One Towel Essity 669334 167 1314 1070 979 1.23 1.34 1.09 Scott Calorie Light Towel K-C 730365 183 1848 1254 1067 1.47 1.73 1.17 Sparkle Towel G-P 792 396 198 18621371 1157 1.36 1.62 1.19 Scott Clean Care Bath Tissue K-C 466 233 1161348 602 474 2.25 2.88 1.28 Angel Soft Bath Tissue G-P 765 383 191 1190763 613 1.56 1.94 1.24 Inventive 1 Bath Tissue — 803 402 201 2193 928591 2.36 3.71 1.57 Inventive 2 Bath Tissue — 710 355 177 1585 691 4912.29 3.23 1.41

The tissue products of the present invention, in particular embodiments,may be manufactured by a process whereby the top and bottom plies areembossed such that when they are combined, the first embossments of thetop ply form dome-like regions there between and the second embossmentsof the bottom ply are nested within, and support, the dome-like regions.This requires an embossing process in which the top and bottom plies areembossed in a synchronized manner in order to ensure the desired nestingarrangement.

To produce multi-ply tissue products, multiple base tissue sheets areprepared and then combined using well known processing machines(converting machines) which include operations such as unwinding thebase tissue sheets, calendering, printing, embossing, bonding ofindividual plies to be combined together as well as cutting, perforationand folding. It is particularly preferred that one or more base sheetsare embossed during formation of the product. An embossing process iscarried out in the nip between an embossing roll, also referred toherein as a patterned roll, and an anvil roll, also referred to hereinas a counter roll. The embossing roll can have protrusions on itscircumferential surface leading to embossments in the paper web.

In certain embodiments the tissue products of the present invention maybe manufactured from two or more base sheet webs, such as two, three orfour base sheet webs that are combined together and embossed using anembossing technique commonly referred to as DESL (Double EmbossingSingle Lamination), which in certain instances may be arranged so as toprovide a nested configuration, as described in more detail below. Inthe DESL process, a first web is directed through the nip between anembossing roll and an anvil roll. In this nip the web is provided withan embossing pattern. Thereafter, an application roll for adhesiveapplies adhesive to those parts of the first web at which there areprotruding embossing elements in the embossing roll. The adhesive istransported from an adhesive bath via an adhesive transfer roll to theapplication roll. A second web is transported to the first web andadhesively bonded to the first web in the nip between the so-calledmarrying roll and the embossing roll. The adhesive bonding takes placeat those portions at which the adhesive was applied.

The process further comprises an additional pair of rolls consisting ofa second embossing roll and a second anvil roll. The additional pair ofrolls serves to emboss the second web before it is adhesively bonded tothe first web using the marrying roll. Typically, the additional pair ofrolls is placed close to the first pair of rolls and the marrying roll.Especially when using the so-called Nested-method, such closearrangement is important. The Nested-method can be considered as aspecial case of the general DESL-manufacturing method. For theNested-method the embossing elements of the first embossing roll and theembossing elements of the second embossing roll are arranged such thatthe embossed elements of the first embossed ply and the embossedelements of the second embossed ply fit into each other similar to agearing system. This serves to achieve a mutual stabilization of the twoplies. However, for the DESL manufacturing method such correlationbetween the embossed elements of the first, upper ply, and the second,lower ply, does not have to apply.

Turning now to FIG. 7, to form a three-ply tissue product 200 comprisingfirst, second and third plies 101, 102, 103, first and second plies 102,103 are unwound from first and second parent rolls 104, 106 and pliedtogether prior to embossing and the third ply 101 is unwound from athird parent roll 107. In certain instances, one or plies may beoptionally pre-embossed in a first pre-embossing station or be subjectedto other converting steps, such as calendering or slitting.

FIG. 8 illustrates a similar process as that illustrated in FIG. 7,except that the bottom ply comprises two separate plies 101, 105, whichare unwound from a single parent roll 107 prior to embossing. In thismanner the tissue product 200 has four plies 101, 102, 103 and 105.

The embossing operation of the present invention utilizes an embossingroll and an anvil that create a nip pressure, when engaged with oneanother to form an embossing nip, sufficient to create deformations(embossments) in a fibrous structure present within the embossing nip.The embossing roll generally comprises a plurality of protrusions on itsouter surface where the protrusions form an embossing pattern. Forexample, as illustrated in FIG. 7, the first and second plies 102, 103are directed into the first nip 110 of a first embossing station thatincludes a first embossing roll 111 and an anvil roll 112. In the nipbetween the first embossing roll 111 and anvil roll 112, the first andsecond plies 102, 103 receive a first embossing pattern by being broughtinto contact with first protuberances 115 disposed on the surface of thefirst embossing roll 111.

In particular embodiments, the embossing roll is made of metal,especially steel, hard plastics materials or hard rubber. In case ofplastics, very hard plastic material can be preferred, alternatively aresin material is also possible. In particular embodiments, the anvilroll is made of rubber like EPDM or

NBR (acrylonitrile-butadiene rubber), paper or steel. The rubber canhave a hardness between 20 and 85 Shore A, preferably between 35 and 60Shore A and most preferably a hardness of about 45 Shore A.

The embossing roll may be made by any suitable process known in the art.Non-limiting examples of suitable processes include laser engraving hardplastic (ebonite) or ceramic or other material suitable for laserablation to remove material and create embossing elements, chemicalengraving of steel or other materials to remove material and createembossing elements, machining aluminum or steel or other metals toremove material and create embossing elements, metallizing processes tobuild up embossing elements, sintering processes to build up embossingelements and/or other means known in the art to remove material or buildup material and achieve a surface topography with the desired patternand clearances between mating embossing elements.

The bottom ply 101, also referred to herein as the third ply, is unwoundfrom a third parent roll 107 and introduced into the nip 120 formedbetween a second embossing roll 121 and a second anvil roll 122 whichform a second embossing station. As regards the possible materials forthe second embossing roll 121 and a second anvil roll 122, the samematerials as described above with reference to the first embossing roll111 and the first anvil roll 112 also apply. Upon passing through theembossing nip 120 the bottom ply 101 is provided with a second embossingpattern, which is preferably different than the pattern applied by thefirst embossing station. The embossing pattern is imparted to the bottomply 101 by contacting it with a plurality of second protuberances 125disposed on the second embossing roll 121.

The process may further comprise an application device 145, which mayinclude an applicator roll 147 for applying functional substances 148 tothe second ply 102 after it exits the first embossing nip 110. Suchapplicator devices are well known in the art and commonly used for theapplication of adhesives or colored substances. For example, the processmay comprise an applicator roll 147 which contacts the protrusions onthe second ply 102 while supported by the first embossing roll 111.

In a particularly preferred embodiment, an adhesive is applied by theapplication device, which may comprise an adhesive applicator rollrunning against the first embossing roll. For laminating the single websof material together, different types of adhesive can be used. Suitableadhesives are, inter alia, glue on the basis of starch or modifiedstarch like, for example, methyl cellulose or carboxylated methylcellulose, and adhesively acting polymers on the basis of syntheticresins, caoutchouc, polypropylene, polyisobutylene, polyurethane,polyacrylates, polyvinyl acetate or polyvinyl alcohol. Such adhesivescan also contain coloring agents in order to improve the opticalappearance of the finished products. Frequently, water-based glues areused for laminating together paper layers.

The first embossing roll 111 and the second embossing roll 121 areoperated in registration with one another which means that both rollshave to be operated in a synchronized manner such that the embossedthird ply 101 leaving the second embossing roll 121 can be directed in apredetermined positional relationship onto the first and second plies102, 103 still on the surface of the first embossing roll 111. In thisway, the first, second and third plies 101, 102, 103 are combined toform a subunit—the bottom ply embossments nest into the dome-likestructures formed by the embossing pattern of the first and secondplies.

Further, a marrying roll 152 runs against the first embossing roll 111such that the subunit including the first and second plies 102, 103 andoptionally a glue applied to a part of the surface of the second ply 102can be brought in contact with the bottom ply 101. In this manner thebottom ply 101 is laminated to the middle ply 102 in a third nip 124formed between the first embossing roll 111 and the marrying roll 152.

In use, the embossments formed on the bottom ply by the second embossingroll are registered with the dome-like structures disposed on an uppertissue ply. Registration in this manner is possible since the firstembossing roll and the second embossing roll are preferably run inregistration with one another. To facilitate this arrangement, thesecond embossing roll may be provided with a plurality of discrete,oval-shaped protrusions that generate the second embossments on the atleast one bottom ply. The second embossments nest into the dome-likestructures of the upper ply and may be arranged to stabilize thedome-like structures.

With reference now to FIG. 9, one example of an embossing pattern 200useful in the present invention is illustrated. The pattern 200 isparticularly useful for embossing an upper ply of a tissue productaccording to the present invention. The embossing pattern 200 comprisesa plurality of discrete circular protrusions 202, also referred to asembossing elements, which in the illustrated embodiment are similarlysized and shaped. The discrete circular protrusions 202 are arranged toform embossing elements 205 a, 205 b, which may be further arranged toform the embossing pattern 200. In certain preferred embodiments, theembossing pattern 200 comprises a plurality of elements 205 that aresubstantially aligned with one another along an axis 210, which may beorientated in the machine direction (MD). The axis 210 may furtherdivide individual elements into symmetrical first and second halves 212,214.

When used to manufacture a tissue product, the embossing elements, whichin the illustrated embodiment are a plurality of discrete circularprotrusions 202 arranged to form elements 205, form a discontinuous lineembossment in the tissue ply where the embossments are relatively deepwith relatively broad upper portions and narrow lower portions. Theelements 205 may further be designed such that they have an unembossedarea that may form dome-like structures in the resulting tissue product.The portion of the embossing pattern 200 corresponding to the dome-likestructures, generally identified as 215 in FIG. 9, are free fromprotrusions.

Between adjacent elements 205, the pattern 200 may include regions 220that are substantially free from embossing elements. Such regions maycorrespond to unembossed regions of the resulting embossed first plyexemplified by reference numeral 38 in FIG. 1.

An embossing element 205 useful in embossing a tissue ply, particularlya top ply in a multi-ply product, is illustrated in further detail inFIGS. 10-12. The element 205 is formed from a plurality of embossingelements 202. The embossing elements 202 generally extend above the rollsurface 250 a given height and are arranged to form a discontinuous lineto create a flower-shaped element 205. The flower-shaped element 205 issymmetrical, having an axis that divides the element into symmetricalfirst and second halves 212, 214.

FIG. 13 shows a second embossing pattern 300 that may be applied to asecond embossing roll and used to emboss the bottom ply of a tissueproduct according to the present invention. The pattern 300 comprises aplurality of discrete protrusions 302. The discrete protrusions 302 arearranged to form a discontinuous line and define embossing elements 305a, 305 b, having an outer perimeter 320. The elements 305 may be alignedwith one another along an axis 310 to form the pattern 300. Further, theaxis 310 may divide individual elements 305 into symmetrical first andsecond halves 311, 313.

In addition to the discrete protrusions 302 forming the elementperimeter 320, the embossing element 305 may further comprise aplurality of discrete protrusions, such as protrusions 314 a-314 c,generally disposed within the perimeter 320. The protrusions may bearranged such that they stabilize the dome-like structures of an uppertissue ply when producing a multi-ply tissue product according to thepresent invention.

Test Methods Microscopy

Tissue products produced according to the present invention may beanalyzed by microscopy as described herein. Paritcularly, thethree-dimensional surface topography and embossments may be analzyed bygenerating and analyzing product 3-D surface maps and cross-sections,such as those illustrated in FIGS. 4A-6C. The images are taken using aVHX-1000 Digital Microscope manufactured by Keyence Corporation ofOsaka, Japan. The microscope is equipped with VHX-5000 CommunicationSoftware Ver 1.5.1.1. The lens is an ultra-small, high performance zoomlens, VH-Z20R/Z20T.

The tissue product sample to be analyzed should be an undamaged, flat,and include representative embossments. A normal sheet of bath tissue,approximately 4 inches×4 inches in size, works well.

A three-dimensional image of the sample is obtained as follows:

1. Turn the digital microscope on and follow standard procedures for XYstage Initialization [Auto].

2. Turn the microscope magnification to x100.

3. Place the tissue product sample on the stage with the firstembossments facing up toward the lens.

4. If the fabric does not lie flat, place weights as needed along theperimeter to make fabric lie flat against the stage surface.

5. Use the focus adjustment to bring the fabric into sharp focus.

6. Select “Stitching” in the main menu. Select “3D stitching.”

7. Set the stitching method by selecting “Stitch around the currentposition.”

8. Select the Z set to set the upper and lower composition range. Theupper limit should be set by going higher than the highest focal pointthat is clear. The lower limit should be set by going lower than thelowest focal point that is clear. After setting the upper and lowerrange, click OK.

9. Select “Start stitching” to begin accusation of the image.

10. In the 3D menu, select “Height/Color view” to identify dome-likefeatures with the highest degree of topography.

11. In the 3D menu, select “Profile.”

12. With the “Profile line” tab selected obtain a cross-section of thetissue sample identified in Step 10, select “Line” and using the cursorto draw a line across the identified portion of the sample. The lineshould bisect at least three adjacent first embossments, such as lineA-A of FIG. 6B. The peaks on the right and left side of the firstembossments should be relatively planar (difference in height less than10%) such as points 47 a and 49 a of FIG. 6C. If the height differencebetween the peaks is more than 10% select another first embossment tomeasure.

To measure various embossment parameters, such as minimum and maximumheights and the distanced there between:

13. Select “Assist Tools.”

14. Select “Max” tool to identify the maximum point to the right of thefirst embossment, such as point 49 a to the right of the firstembossment 24 a of FIG. 6C.

15. Select “Max” tool to identify the maximum point to the left of thefirst embossment, such as point 47 a to the left of the first embossment24 a of FIG. 6C.

16. Select “Min” tool to identify the minimum point in the firstembossment, such as point 45a of the first embossment 24a of FIG. 6C.

17. Select “MidPoint” tool to determine the midpoint between the maximumpeak on the right side of the first embossment and the first embossmentminimum, such as the point M2 between the embossment minimum 45 andright side maximum 49 of the first embossment 24 of FIG. 5C.

18. Select “MidPoint” tool to determine the midpoint between the maximumpeak on the left side of the first embossment and the first embossmentminimum, such as the point M1 between the embossment minimum 45 and leftside maximum 47 of the first embossment 24 of FIG. 5C.

19. Select “MidPoint” tool to determine the midpoint between themidpoint determined in step 17 and the minimum of the first embossment.This point is 25 percent of the distance between the maximum peak on theright side of the first embossment and the first embossment minimum,such as the point Q2 between the embossment minimum 45 and right sidemaximum 49 of the second embossment 24 of FIG. 5C.

20. Select “MidPoint” tool to determine the midpoint between themidpoint determined in step 18 and the minimum of the first embossment.This point is 25 percent of the distance between the maximum peak on theleft side of the first embossment and the first embossment minimum, suchas the point Q1 between the embossment minimum 45 and left side maximum47 of the second embossment 24 of FIG. 5C.

To calculate the cross-sectional area of various portions of theembossments, such as A₁₀₀, A₅₀ and A₂₅:

21. Select “Assist Tools.”

22. Select “CrsSct(bottom).” Check “Measure at arbitrary point” box.

23. Select the maximum point to the right of the first embossment (step14), select the maximum point to the left of the first embossment (step15). Set the right line to the right of the right side wall of theembossment. Set the left line to the left of the left side wall of theembossment. This value is A₁₀₀.

24. Select the midpoint to the right of the first embossment (step 17),select midpoint to the left of the first embossment (step 18). Set theright line to the right of the right side wall of the embossment. Setthe left line to the left of the left side wall of the embossment. Thisvalue is A₅₀.

25. Select the midpoint of the midpoint to the right of the firstembossment (step 19), select midpoint of the midpoint to the left of thefirst embossment (step 20). Set the right line to the right of the rightside wall of the embossment. Set the left line to the left of the leftside wall of the embossment. This value is A₂₅.

To measure the height of the embossments:

26. In the Measurement Tools, ensure the “Measure” tab is selected.

27. Select the “Pt-Pt” tool, then select Vertical from the pull-downmenu.

28. Select the maximum point to the right of the first embossment (step14), then select the minimum point (Step 16), then click on the place onthe screen to display the measurement. This value will be used tocalculate H₁₀₀ as described below and is the height (H2) between points45 and 49 of FIG. 4C.

29. Select the maximum point to the left of the first embossment (step15), then select the minimum point (Step 16), then click on the place onthe screen to display the measurement. This value will be used tocalculate H₁₀₀ as described below and is the height (H1) between points45 and 47 of FIG. 4C.

30. Select the midpoint to the right of the embossment (step 17), thenselect the minimum point (step 16), then click on the place on thescreen to display the measurement. This value will be used to calculateH₅₀ as described below and is the height (H4) between points 45 and M2of FIG. 5C.

31. Select the midpoint to the left of the embossment (step 18), thenselect the minimum point (step 16), then click on the place on thescreen to display the measurement. This value will be used to calculateH₅₀ as described below and is the height (H3) between points 45 and M1of FIG. 5C.

32. Select the midpoint of the midpoint to the right of the embossment(step 19), then select the minimum (step 16), then click on the place onthe screen to display the measurement. This value will be used tocalculate H₂₅ as described below and is the height (H6) between points45 and Q2 of FIG. 5C.

33. Select the midpoint of the midpoint to the left of the embossment(step 20), then select the minimum (step 16), then click on the place onthe screen to display the measurement. This value will be used tocalculate H₂₅ as described below and is the height (H5) between points45 and Q1 of FIG. 5C.

Various parameters of the tissue product may be calculated from theforegoing measurements as indicated below:

34. To calculate H₁₀₀ average the values measured in steps 28 and 29.

35. To calculate H₅₀ average the values measured in steps 30 and 31.

36. To calculate H₂₅ average the values measured in steps 32 and 33.

37. To calculate W₁₀₀ divide A₁₀₀ (step 23) by H₁₀₀ (as determined instep 34).

38. To calculate W₅₀ divide A₅₀ (step 24) by H₅₀ (as determined in step35).

39. To calculate W₂₅ divide A₂₅ (step 25) by H₂₅ (as determined in step36).

Sheet Bulk

Sheet Bulk is calculated as the quotient of the dry sheet caliper (μm)divided by the basis weight (gsm). Dry sheet caliper is the measurementof the thickness of a single tissue sheet measured in accordance withTAPPI test methods T402 and T411 om-89. The micrometer used for carryingout T411 om-89 is an Emveco 200-A Tissue Caliper Tester (Emveco, Inc.,Newberg, Oreg.). The micrometer has a load of 2 kilo-Pascals, a pressurefoot area of 2,500 square millimeters, a pressure foot diameter of 56.42millimeters, a dwell time of 3 seconds, and a lowering rate of 0.8millimeters per second.

Tensile

Tensile testing was done in accordance with TAPPI test method T-576“Tensile properties of towel and tissue products (using constant rate ofelongation)” wherein the testing is conducted on a tensile testingmachine maintaining a constant rate of elongation and the width of eachspecimen tested is 3 inches. More specifically, samples for dry tensilestrength testing were prepared by cutting a 3±0.05 inch (76.2±1.3 mm)wide strip in either the machine direction (MD) or cross-machinedirection (CD) orientation using a JDC Precision Sample Cutter(Thwing-Albert Instrument Company, Philadelphia, Pa., Model No. JDC3-10, Serial No. 37333) or equivalent. The instrument used for measuringtensile strengths was an MTS Systems Sintech 11S, Serial No. 6233. Thedata acquisition software was an MTS TestWorks® for Windows Ver. 3.10(MTS Systems Corp., Research Triangle Park, N.C.). The load cell wasselected from either a 50 Newton or 100 Newton maximum, depending on thestrength of the sample being tested, such that the majority of peak loadvalues fall between 10 to 90 percent of the load cell's full scalevalue. The gauge length between jaws was 4±0.04 inches (101.6±1 mm) forfacial tissue and towels and 2±0.02 inches (50.8±0.5 mm) for bathtissue. The crosshead speed was 10±0.4 inches/min (254±1 mm/min), andthe break sensitivity was set at 65 percent. The sample was placed inthe jaws of the instrument, centered both vertically and horizontally.The test was then started and ended when the specimen broke. The peakload was recorded as either the “MD tensile strength” or the “CD tensilestrength” of the specimen depending on direction of the sample beingtested. Ten representative specimens were tested for each product orsheet and the arithmetic average of all individual specimen tests wasrecorded as the appropriate MD or CD tensile strength of the product orsheet in units of grams of force per 3 inches of sample. The geometricmean tensile (GMT) strength was calculated and is expressed asgrams-force per 3 inches of sample width. Tensile energy absorbed (TEA)and slope are also calculated by the tensile tester. TEA is reported inunits of gm.cm/cm². Slope is recorded in units of kg. Both TEA and Slopeare directionally dependent and thus MD and CD directions are measuredindependently. Geometric mean TEA and geometric mean slope are definedas the square root of the product of the representative MD and CD valuesfor the given property.

Multi-ply products were tested as multi-ply products and resultsrepresent the tensile strength of the total product. For example, atwo-ply product was tested as a two-ply product and recorded as such. Abasesheet intended to be used for a two-ply product was tested as twoplies and the tensile recorded as such. Alternatively, a single ply maybe tested, and the result multiplied by the number of plies in the finalproduct to get the tensile strength.

Embodiments

In a first embodiment the present invention provides a multi-ply tissueproduct comprising a first ply having a first surface and a plurality ofdiscrete, spaced apart, dot embossments disposed thereon and a pluralityof dome-like structures disposed between the spaced apart dotembossments and a second ply having a first surface and a plurality ofdiscrete embossments disposed thereon, wherein the dot embossments havea height (H₁₀₀) greater than 500 μm and an average width at 25% height(W₂₅) less than about 600 μm.

In a second embodiment the present invention provides the product of thefirst embodiment wherein the tissue product has a geometric mean tensile(GMT) strength from about 800 to about 1,700 g/3″.

In a third embodiment the present invention provides the product of thefirst or the second embodiments wherein the tissue product consists ofthree plies and has a basis weight from about 30 to about 50 grams persquare meter (gsm).

In a fourth embodiment the present invention provides the product of anyone of the foregoing embodiments wherein the first and second plies havea basis weight from about 10 to about 20 gsm.

In a fifth embodiment the present invention provides the product of anyone of the foregoing embodiments wherein the tissue product has a sheetbulk from about 7.0 to about 11.0 cubic centimeters per gram (cc/g).

In a sixth embodiment the present invention provides the product of anyone of the foregoing embodiments wherein the tissue product is spirallywound around a core to yield a rolled tissue product having a roll bulkfrom about 8.0 to about 13.0 cc/g.

In a seventh embodiment the present invention provides the product ofany one of the foregoing embodiments wherein the dot embossments have aH₁₀₀ from 700 to about 1,000 μm.

In an eighth embodiment the present invention provides the product ofany one of the foregoing embodiments wherein the dot embossments have aratio of average width at 100% height (Moo) to W₂₅ from about 3.00 toabout 4.00.

In a ninth embodiment the present invention provides the product of anyone of the foregoing embodiments wherein the dot embossments have aratio of average width at 50% height (W₅₀) to W₂₅ greater than about1.40.

In a tenth embodiment the present invention provides the product of anyone of the foregoing embodiments wherein the tissue product has a basisweight of about 60 gsm or less and a GMT less than about 1,500 g/3″ andthe dot embossments have a W₅₀ less than about 1,000 μm and an averageheight at 50% (H₅₀) greater than about 350 μm.

1. An embossed multi-ply tissue product comprising a first ply having afirst surface and a plurality of discrete, spaced apart, dot embossmentsdisposed thereon and a plurality of dome-like structures disposedbetween the spaced apart dot embossments and a second ply having a firstsurface and a plurality of discrete embossments disposed thereon, eachof the discrete embossments bounded by spaced apart dot embossments andin registration with a dome-like structure, wherein the dot embossmentshave a height (H₁₀₀) greater than 500 μm and an average width at 25%height (W₂₅) less than about 600 μm.
 2. The embossed multi-ply tissueproduct of claim 1 wherein the tissue product has a geometric meantensile (GMT) strength from about 800 to about 1,700 g/3″.
 3. Theembossed multi-ply tissue product of claim 1 wherein the tissue productconsists of three plies and has a basis weight from about 30 to about 50grams per square meter (gsm) and a sheet bulk from about 7.0 to about11.0 cubic centimeters per gram (cc/q).
 4. The embossed multi-ply tissueproduct of claim 1 further comprising unembossed regions region havingan upper surface lying in a first tissue product surface plane and thedome-like structure having an upper surface lying in a second tissueproduct surface plane, wherein the second tissue product surface planeis at least 100 μm above the first tissue product surface plane. 5.(canceled)
 6. The embossed multi-ply tissue product of claim 1 whereinthe tissue product is spirally wound around a core to yield a rolledtissue product having a roll bulk from about 8.0 to about 13.0 cc/g. 7.The embossed multi-ply tissue product of claim 1 wherein the dotembossments have a H₁₀₀ from 700 to about 1,000 μm.
 8. The embossedmulti-ply tissue product of claim 1 wherein the dot embossments have aratio of average width at 100% height (W₁₀₀) to W₂₅ from about 3.00 toabout 4.00.
 9. The embossed multi-ply tissue product of claim 1 whereinthe dot embossments have a ratio of average width at 50% height (W₅₀) toW₂₅ greater than about 1.40.
 10. The embossed multi-ply tissue productof claim 1 wherein the tissue product has a basis weight of about 60 gsmor less and a GMT less than about 1,500 g/3″ and the dot embossmentshave a W₅₀ less than about 1,000 μm and an average height at 50% (H₅₀)greater than about 350 μm.
 11. A multi-ply tissue product comprisingfirst and second tissue plies, the first ply having embossed andunembossed regions, the embossed regions comprising a plurality of firstembossments arranged in an embossing pattern and defining a dome-likeregion there between, the unembossed region having an upper surfacelying in a first tissue product surface plane and the dome-likestructure having an upper surface lying in a second tissue productsurface plane, wherein the second tissue product surface plane is atleast 100 pm above the first tissue product surface plane.
 12. Themulti-ply tissue product of claim 11 further comprising a second plyhaving a plurality of second embossments disposed thereon, wherein atleast one of the plurality of second embossments nests into thedome-like structure and is bounded by at least two spaced apart firstembossments.
 13. The multi-ply tissue product of claim 12 furthercomprising a third ply disposed between the first and second plies,wherein the third ply comprises embossments registered with the firstembossments and the third ply is bonded to the first ply.
 14. Themulti-ply tissue product of claim 12 wherein the first embossments arediscrete dot embossments and the second embossments are discreteembossments.
 15. The multi-ply tissue product of claim 11 wherein thetissue product has a geometric mean tensile (GMT) strength from about800 to about 1,500 g/3″ and a basis weight from about 30 to about 80grams per square meter (gsm).
 16. (canceled)
 17. The multi-ply tissueproduct of claim 11 wherein the tissue product has sheet bulk from about7.0 to about 11 cubic centimeters per gram (cc/g).
 18. The multi-plytissue product of claim 11 wherein the tissue product is spirally woundaround a core to yield a rolled tissue product having a roll bulk fromabout 8.0 to about 13 cc/g.
 19. The multi-ply tissue product of claim 11wherein the first embossments have a H₁₀₀ from 700 to about 1,000 μm.20. The multi-ply tissue product of claim 11 wherein the firstembossments have a ratio of average width at 100% height (W₁₀₀) to W₂₅from about 3.00 to about 4.00.
 21. The multi-ply tissue product of claim11 wherein the first embossments have a ratio of average width at 50%height (W₅₀) to W₂₅ is greater than about 1.40.
 22. The multi-ply tissueproduct of claim 11 wherein the product has a basis weight less of about60 gsm or less and a GMT less than about 1,600 g/3″ and the first dotembossments have a W₅₀ less than about 1,000 μm and an average height at50% (H₅₀) greater than about 350 μm.